Official Publication of the Academy of Family Physicians of India
Vol 2 / Issue 1 / January 2013
and Primary Care
Journal of Family Medicine and Primary Care 104 January 2013 : Volume 2 : Issue 1
Purple urine bag syndrome (PUBS) is rare and was first reported in
and is signified by purple discoloration of the urine usually
seen in women and chronically debilitated patients with long
term indwelling urinary catheters.[2,3]
PUBS can be distressing for
patients, family members and healthcare workers who are unaware
of this association. This condition is often associated with urinary
tract infection. Discolouration of the urine bag is due to the
presence of indigo and indirubin pigments which precipitate and
react with the synthetic materials of the catheter and urinary bag.
We present a case report of this rare phenomenon.
An 86‑year‑old woman had a history of osteoporosis and bilateral
fracture of neck femur for two years. Her daily activity was limited
and she was bedridden most of the day. She could sit for a while
with a caregiver’s help [Figure 1].
She had Foley catheterization for one year because of neurogenic
bladder. She was also suffering from constipation from her early
age and it became severe enough in last two years. Urine with
purple sediment was found in the urine bag one day before
admission [Figure 2].
She did not have fever or a history of drug administration
before admission. The patient had a history of recurrent
urinary tract infections (UTIs) in the past. Physical examination
revealed diffuse tenderness on palpation of the abdomen.
Other examinations did not indicate any other noteworthy
symptoms. The urinalysis showed alkaline urine with the urinary
sediment contained 5-7 white blood cells/high‑power‑field. She
was admitted under the impression of urinary tract infection
and constipation. The patient was empirically started on oral
cefuroxime. Urine cultures yielded Escherichia Coli and growth
was greater than 105
/mL. The antibiotic therapy was changed to
ceftriaxone 1 gm intravenous injection every day and gentamicin
80 mg intravenous injection 8 hourly according to antibiotic
sensitivity tests of the urine cultures. A glycerol containing oral
preparation was given for her constipation. The Foley catheter
was also changed. The purple urine disappeared and the following
urinalysis was sterile. She was discharged in stable condition.
PUBS is rare and was first reported in 1978.
It is a rare
manifestation of urinary tract infection. It is an uncommon
occurrence, but prevalence of PUBS has been reported to be
as high as 9.8% in institutionalized patients with long‑term
indwelling urinary catheter use.[2,3,4]
PUBS have been shown to
be associated with the female gender, alkaline urine, constipation,
institutionalization and the use of plastic urinary catheter and
Higher bacterial load in urine, in combination with
the above factors, facilitates the development of PUBS. Most
Purple Urine Bag Syndrome
Ahmed Al Montasir, Ahmed Al Mustaque1
Family Medicine Diploma, University of Science and Technology, Chittagong, Family Physician, Sofia Ismail Memorial Medical
Centre, Bogra, 1
Diploma in Orthopaedic Surgery University of Rajshahi, Consultant Orthopaedic Surgeon, Sofia Ismail
Memorial Medical Centre, Bangladesh
Address for correspondence: Dr. Ahmed Al Montasir,
Sofia Ismail Memorial Medical Centre, Gohail Road, Sutrapur,
Bogra 5800, Bangladesh.
Purple urine bag syndrome (PUBS) is rare disease entity, occurs predominantly in constipated women, chronically catheterized
and associated with bacterial urinary infections that produce sulphatase/phosphatase. The etiology is due to indigo (blue) and
indirubin (red) or to their mixture that becomes purple. We present a case report of this rare phenomenon occurring in an 86‑year‑old
Keywords: Chronic urinary catheterisation, indigo, indirubin, purple urine bag syndrome, urinary tract infection
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Montasir and Mustaque: Purple urine bag syndrome
Journal of Family Medicine and Primary Care 105 January 2013 : Volume 2 : Issue 1
authors believe that purple urine is a mixture of indigo and
indirubin which are derived from the metabolites of tryptophan.
Tryptophan is metabolized in the gastrointestinal tract by gut
bacteria and it produces indole that is absorbed into portal
circulation. Indole is converted into indoxyl sulphate in the liver.
Most indoxyl sulphate is excreted into the urine and digested
into indoxyl by indoxyl sulphatase produced by some bacteria.
Indoxyl turns into indigo (blue color) and indirubin (red color)
in alkaline urine, and these colors then mix to form a purple
However, there were some patients who presented with
a purple urine bag without indicanuria and the violet pigment may
be either a steroidal or bile acid conjugate.
is commonly associated with bacterial overgrowth in the colon
which increases the conversion of tryptophan into indole.
Catheter associated urinary tract infection increases the conversion
of indoxyl sulphate into indoxyl. So, PUBS is most often observed
in chronically catheterized and constipated people.[4,5]
bacterial species have been reported in association with PUBS
including Providencia stuartii, Providencia rettgeri, Klebsiella pneumoniae,
Proteus species, Escherichia coli, Enterococcus species, Morganella morganii,
and Pseudomonas aeruginosa.[5,6]
In our case, the patient had chronic
constipation and the urine culture yielded Escherichia coli. It is
interesting to note that despite the common occurrence of
urinary tract infections in patients with risk factors for PUBS,
this interesting syndrome is rarely encountered. There are a
few possible reasons. PUBS probably require the simultaneous
presence of various factors: The presence of urinary tract
infection caused by sulphatase‑and phosphatase‑producing
bacteria, the presence of high tryptophan in the diet for the
formations of the essential pigments, and being catheterised.
It has been shown that not all bacteria organisms of the same
species produce the phosphatase and sulphatase enzymes required
for the formation of the responsible pigments.[5,7]
a certain concentration of the pigments may be required for the
precipitations to become visible. The presence of alkaline urine,
and also the type of materials used to manufacture the urinary
catheter and bag may be important factors.[5,7]
in the presence of acidic urine has also been reported.
generally a benign process. Despite this fact, it is distressing for
family, friends, and healthcare workers who are unaware of this
phenomenon and tend to become unusually alarmed because of
the sudden inexplicable discoloration of the urine and sometimes
the urine bag. Nevertheless, physicians should be aware of the
fact that this syndrome signals underlying recurrent UTIs, due to
improper care of the urinary catheters and improper sanitation.
Although relatively benign and easily treatable, it can be associated
with significant morbidity and mortality.[1,2,7]
1. Khan F, Chaudhry MA, Qureshi N, Cowley B. Purple urine
bag syndrome: An Alarming Hue? A Brief Review of the
Literature. Int J Nephrol 2011;2011:419213.
2. Lin CH, Huang HT, Chien CC, Tzeng DS, Lung FW. Purple
urine bag syndrome in nursing homes: Ten elderly
case reports and a literature review. Clin Interv Aging
3. Su FH, Chung SY, Chen MH, Sheng ML, Chen CH, Chen YJ,
et al. Case analysis of purple urine‑bag syndrome at a
long‑term care service in a community hospital. Chang
Gung Med J 2005;28:636‑42.
4. Lin HH, Li SJ, Su KB, Wu LS. Purple urine bag syndrome:
A Case Report and Review of the Literature. J Intern Med
5. Dealler SF, Hawkey PM, Millar MR. Enzymatic degradation of
urinary indoxyl sulfate by Providencia stuartii and Klebsiella
pneumoniae causes the purple urine bag syndrome. J Clin
6. Ollapallil J, Irukulla S, Gunawardena I. Purple urine bag
syndrome. ANZ J Surg 2002;72:309‑10.
7. Jones RA, Deacon HJ, Allen SC. Two cases and a short
discussion of purple urine bag syndrome. CME Geriatr Med
Figure 1: Patient having purple urine bag syndrome Figure 2: Purple colored urine in urine bag
How to cite this article: Al Montasir A, Al Mustaque A. Purple urine bag
syndrome. J Fam Med Primary Care 2013;2:104-5.
Source of Support: Nil. Conflict of Interest: None declared.